As shown in FIG. 9, a conventional luminous pedal is mounted on a screwing portion 61 of a crank 6 of a bicycle, and the crank 6 has a connecting portion 62 formed on one end thereof opposite to the screwing portion 61 so as to couple with a shaft 63. The luminous pedal 5 contains a post 51 for connecting with the crank 6, a base 52 fitted on the post 51, an electricity generating device 53 fixed between the post 51 and the base 52, a plurality of light emitting elements 56 driven by the electricity generating device 53, and a covering member 57 for covering the electricity generating device 53, a chamber 521 formed in the base 52, two slots 522 arranged on two sides of the base 52.
The electricity generating device 53 is defined between the post 51 and the base 52 and includes a magnetic element 54 fitted on the post 51, and a coil member 55 disposed in the chamber 521 of the base 52 and surrounding the magnetic element 54. When the coil member 55 rotates relative to the magnetic element 54, an induced voltage is outputted. The magnetic element 54 is a circularly permanent magnet, and the coil member 55 has a body 551 with guiding lines, a first electrode piece 552 and a second electrode piece 552′ for outputting the induced voltage. The first electrode piece 552 and the second electrode piece 552′ electrically connect with the plurality of light emitting elements 56. The coil member 55 also has a first pole portion 553 and a second pole portion 553′, wherein the first pole portion 553 and the second pole portion 553′are formed in a triangle shape, spaced apart from each other, and biased against the body 551.
However, when a rider steps the luminous pedal slowly, the electricity generating device 53 cannot generate enough induced voltage, so the plurality of light emitting elements 56 cannot be driven by the induced voltage of the electricity generating device 53 to emit lights.
The present invention has arisen to mitigate and/or obviate the afore-described disadvantages.